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Long Underwear for Men

Rating: 5.0 out of 5.0
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Select Modern or Athletic Fit

ALPHX Every Day Comfort Union PantLayer or Lounge?  You decide.

We designed our union pants with the same premium, ethically sourced material as our underwear, and we don't skip on any of the details either.  Our signature 120° button-front fly is angled for easy to open, secure when closed functionality.  2 flat back-seams follow the contours of your seat preventing uncomfortable wedgies.  They have a 30.5-inch inseam (size medium) and are narrow at the ankle, making them perfect for wearing as a base layer under clothes. Plus, they're lightweight, cozy, and breathable, so you won't sweat while wearing them under a pair of pants or hanging out at home. 

Our Contemporary MDRN (Modern) Fit is available in sizes XS-XXL, and our ATHLTC (Athletic) Fit comes in S-XL with an additional inch of leg circumference for guys with large or muscular thighs.

We encourage you to use our personal FIT FINDER to help you find the right fit for you.

We think it's the most comfortable underwear you will ever wear, but you be the judge: give us a try risk-free with our Be Assured Guarantee.

Be Comfortable

Our Underwear is understated, but never basic. ALPHX is designed for everyday comfort and we think, stylish enough for special occasions too.  You be the judge.  Try a pair risk free with our Be Assured Guarantee.

We start with materials that are soft to the touch:  lightweight breathable natural cotton and modal made from beech tree bark pulp. (Doesn’t sound soft, but believe us when we say it is.) Then, for strength, stretch, and recovery, we combine these two materials with just the right amount of elastane. Our tonal waistband is obnoxious free subtly embossed with our signature ALPHX logo.

  • 56% Cotton, 38% Modal, 6% Elastane
  • Ethically made in Sri Lanka
  • 94% Sustainable. 100% Comfortable
  • 155 GM lightweight, breathable cotton
  • 4-way stretch for movement and recovery
  • Double-lined contoured pouch for comfortable support
  • Back rise slightly higher than front to prevent ride-up
  • 1.5" soft contoured waistband follows your natural curve to prevent pinch and roll down
  • Tear-away labels for tag free comfort
  • Locker loop for convenience


Care Instructions

  • Machine wash cold with similar colors
  • Do not bleach
  • Tumble dry low
  • Do not iron
  • Do not dry clean
  • Do not use fabric softener
Content & Care

    Peace of Mind, Guaranteed


    We don’t think Shipping Costs should come between us. That’s why we offer free shipping on every purchase. Restrictions Apply

    • Free shipping on every order within the U.S.
    • Free shipping on all returns within the U.S. subject to our return policy

    Domestic orders are shipped via USPS First Class: tracking information provided.


    Give ALPHX a risk-free try, and if we’re not for you (we think we’re a catch btw), your purchase is on us. 

    We believe we make a damn good product, but we understand that every man’s body is different, and we may not be right for everyone. That’s why we remove any risk for you to try ALPHX. If it doesn’t work for you, no hard feelings. We’d love to know why so we can continue to improve, but we will happily issue you a refund.  

    Our Be Assured guarantee is good for your first underwear purchase from If you purchased more than one pair, please try one on before removing the others from their packaging. If you don’t like the first pair, the others are still eligible for our standard return policy. 

    Be Assured guarantee is limited to one use per household and must be claimed within 30 days of the original purchase date.

    Request a Be-Assured Refund


    ALPHX underwear in their original, unworn, and unwashed condition may be returned for a refund up to 30 days after the original purchase date. We'll even cover the shipping cost. 

    Request a Return Label


    We've all done it. Not sure between two sizes so you order both and return the one you don't want. Or you order a size, discover it's not quite right and then you have to pay for the size you need, and wait for your return to be received and processed before getting your credit on the one you sent back.

    And maybe you had a code to save on your first purchase that no longer works on buying the size you need, so you pay more. Frustrating, right?

    With ALPHXchange, we won't make you wait until we receive the returned items back before sending you the items you need.

    We'll email you your return label and simultaneously ship out your replacement items at whatever price you paid for your original order. And both the return and the new items ship free.

    ALPHX underwear in their original, unworn, and unwashed condition may be exchanged for an alternate size or color up to 30 days after the original purchase date. We'll even cover the shipping cost. 

    Request an Exchange


    • International orders under $50.00 ship for the flat rate of $5.00. International orders over $50 ship FREE  via International Priority Delivery  (6-10 business days) .  The following Countries are covered by our $5.00 flat rate and Free shipping program: 
      • Åland Islands, Albania, Andorra, Armenia, Belarus, Bosnia & Herzegovina, Faroe Islands, Georgia, Gibraltar, Greenland, Guadeloupe, Guernsey, Iceland, Isle of Man, Jersey, Kosovo, Liechtenstein, Mayotte, Moldova, Monaco, Montenegro, North Macedonia, Norway, San Marino, Serbia, Svalbard & Jan Mayen, Switzerland, Turkey, Ukraine, Vatican City, Australia, Austria, Belgium, Bulgaria, Canada, China, Croatia, Cyprus, Czechia, Denmark, Estonia, Finland, France, Germany, Greece, Hong Kong SAR, Hungary, India, Ireland, Israel, Italy, Japan, Latvia, Lithuania, Luxembourg, Malta, Mexico, Netherlands, New Zealand, Philippines, Poland, Portugal, Réunion, Romania, Singapore, Slovakia, Slovenia, South Korea, Spain, Sweden, Taiwan, United Kingdom
    • Free shipping only applies to Priority International.  
    • You will receive a tracking number to follow your order throughout the process.  
    • Your international shipping includes insurance.  There have been interruptions of this service due to COVID outbreaks.  If this service is not available at the time you place your order, you will be shown alternative shipping methods/carriers and costs associated with them.  We apologize for any inconvenience and are more than happy to answer questions or suggest alternatives. 
    • International orders will be processed with 48 hours of receiving your order: M-F.
    • Delivery options and prices will be displayed at checkout.
    The customer is responsible for any taxes and duties owed.

      Our Be Assured Guarantee applies to International orders as well. We got you. 

      ALPHX underwear in their original, unworn, and unwashed condition may be returned for a refund up to 30 days after the original purchase date. Customers are responsible for all return shipping costs.  

      Timing is estimate only. Any transport delays are unfortunately beyond our control.  You will also be given options for expedited shipping at checkout.











        Customer Reviews

        Based on 5 reviews
        Big Fan

        Big fan of the long underwear! The large fits great and is super comfortable

        Beyond comfortable

        Soft, comfortable and warm. I wear them lounging around the house and they keep me warm outside in the cold weather.

        Great Base Layer!

        These are very comfortable and cute! I can see myself lounging around the house in them or even wearing them out in these could Northeast winters.

        Samuel Fuhrman

        Union Pant

        John I
        Great Pant

        Wore the Union Pant as a base layer on a night of fishing. New England fall temperatures can be chilly but the Union Pant kept me warm the entire night. 10/10!!